conftest/model: Fetch server version and feature level via /register.

This adds zulip_version among the requested event_types to fetch
zulip_version and zulip_feature_level via POST /register API endpoint.

Feature level, a monotonic integer (starts from 1), is introduced in
Zulip 2.2 and is always returned in POST /register from Feature Level 3
along with zulip_version. However, it is likely that some servers might
choose to not adhere to feature level (the adapting code is present in
model's init method).

For testing, this also introduces zuilp_version fixture to test
different components based on the server version and the feature level.

Note: zulip_version fixture is not used, i.e. the server version and the
feature level (using MINIMUM_SUPPORTED_SERVER_VERSION) are hard-coded,
in initial_data fixture on purpose to avoid adding extra tests
unnecessarily.

Test amended.

Fixes #616 partially.

Author: preetmishra

tests/conftest.py

@@ -8,6 +8,9 @@
 from zulipterminal.helper import initial_index as helper_initial_index
 from zulipterminal.ui_tools.boxes import MessageBox
 from zulipterminal.ui_tools.buttons import StreamButton, UserButton
+from zulipterminal.version import (
+    MINIMUM_SUPPORTED_SERVER_VERSION, SUPPORTED_SERVER_VERSIONS,
+)
 
 
 @pytest.fixture(autouse=True)
@@ -312,6 +315,19 @@ def messages_successful_response() -> Dict[str, Any]:
     })
 
 
+@pytest.fixture(
+    params=SUPPORTED_SERVER_VERSIONS,
+    ids=(lambda param:
+         'server_version:{}-server_feature_level:{}'.format(*param))
+)
+def zulip_version(request):
+    """
+    Fixture to test different components based on the server version and the
+    feature level.
+    """
+    return request.param
+
+
 @pytest.fixture
 def initial_data(logged_on_user, users_fixture, streams_fixture):
     """
@@ -467,6 +483,10 @@ def initial_data(logged_on_user, users_fixture, streams_fixture):
         'last_event_id': -1,
         'muted_topics': [],
         'realm_user_groups': [],
+        # Deliberately use hard-coded zulip version and feature level to avoid
+        # adding extra tests unnecessarily.
+        'zulip_version': MINIMUM_SUPPORTED_SERVER_VERSION[0],
+        'zulip_feature_level': MINIMUM_SUPPORTED_SERVER_VERSION[1],
     }
 
 

tests/model/test_model.py

@@ -53,6 +53,10 @@ def test_init(self, model, initial_data, user_profile):
                                                    num_after=10,
                                                    anchor=None)
         assert model.initial_data == initial_data
+        assert model.server_version == initial_data['zulip_version']
+        assert model.server_feature_level == (
+            initial_data.get('zulip_feature_level')
+        )
         assert model.user_id == user_profile['user_id']
         assert model.user_full_name == user_profile['full_name']
         assert model.user_email == user_profile['email']
@@ -136,6 +140,7 @@ def test_register_initial_desired_events(self, mocker, initial_data):
             'muted_topics',
             'realm_user',
             'realm_user_groups',
+            'zulip_version',
         ]
         model.client.register.assert_called_once_with(
                 event_types=event_types,

zulipterminal/model.py

@@ -98,6 +98,11 @@ def __init__(self, controller: Any) -> None:
         # lose any updates while messages are being fetched.
         self._update_initial_data()
 
+        self.server_version = self.initial_data['zulip_version']
+        self.server_feature_level = (
+            self.initial_data.get('zulip_feature_level')
+        )
+
         self.users = self.get_all_users()
 
         subscriptions = self.initial_data['subscriptions']
@@ -936,7 +941,10 @@ def _register_desired_events(self, *, fetch_data: bool=False) -> str:
             'update_message_flags',
             'muted_topics',
             'realm_user',  # Enables cross_realm_bots
-            'realm_user_groups'
+            'realm_user_groups',
+            # zulip_version and zulip_feature_level are always returned in
+            # POST /register from Feature level 3.
+            'zulip_version',
         ]
         event_types = list(self.event_actions)
         try: